Using transcranial direct-current stimulation (tDCS) combined with a complex multisensory-motor dance video game (DVG) task, we investigated a possible role of the middle temporal gyrus (MTG), an integration site of visual and auditory information, on the motor learning efficiency. Eighteen young-adults received any one stimulation type of anodal, cathodal, or sham stimulation and performed DVG for 3 times. The number of timing-accurate steps was evaluated as an index of motor performance over repetitive game play and stimulation conditions. Anodal MTG stimulation increased the post-training performance selectively in participants who had previous experience of musical training or music video game, whereas cathodal MTG stimulation increased the post-training performance in the other novice participants. These results demonstrated differential effect of MTG stimulation on the improvement of timing accuracy in DVG task depending on the previous experience in multisensory-integrative motor task.

Gray matter volulme in periaqueductal gray (PAG) was increased in μ-opioid receptor knockout (MOP-KO) mice reported by voxel-based morphometry in magnetic resonace imaging. PAG is related to pain modulation with ascending autonomic and sensory input. We evaluated the locomotor activity with open-field test for MOP-KO mice. Tweleve wild-type and tweleve MOP-KO mice were used. Kinetic parameter was analyzed from ten minutes movie recorded by homemade video tarcking system. Mean velocity of wild-type and MOP-KO mice is 145.1±26.7mm/sec and 107.0±27.5 mm/sec, respectively, which was significantly defferent. Velocity fluctuation between wild-type and MOP-KO is almost same, according to the coefficient variation of velocity in wild-type and MOP-KO mice, which indicate 0.39±0.06 and 0.40±0.04, respectively. Moving velocity of MOP-KO mice might be reduced as a result of hyperalgesia.

In the hippocampus of rodents during locomotion, 5-12 Hz oscillatory EEG (theta activity) is observed. The hippocampal theta activity plays important role in encoding the animal's position during spatial navigation. It has been reported that frequency and amplitude of the theta activity correlate with the locomotion speed. However, the precise temporal relationship has not been elucidated. To investigate the relationship, we recorded the hippocampal EEG from mice during voluntary locomotion in a virtual corridor. It was confirmed that the hippocampal theta activity occurred during locomotion and its frequency and amplitude positively correlated with the locomotion speed. Time-shift cross-correlation analysis revealed that the change in theta activity was approximately 200 ms ahead to that of locomotion speed. Impact of manipulation of visual feedback to the theta activity was not strong. These results suggest that the hippocampal theta activity is forecasting or attracting instantaneous behavior of the animal.

In order to understand the condition of mild brain injury caused by a blast wave, a technique that can identify a mild brain lesions becomes required. We established a fluorescence imaging method of the brain that underwent a clearing (transparency) treatment of fluorescent neutrophil-expressing mice for evaluation of mild brain injury. We loaded blast waves on fluorescent neutrophil-expressing mice. After extracting the brains, the clearing treatment was carried out based on CUBIC method. Then, neutrophil imaging was performed by fluorescence microscope. We succeeded in constructing a 3D image of neutrophils' distribution of the injured brain. This study revealed that an increase in the neutrophil density at the injury site was consequently visualized. This imaging method enables us to understand microbrain damage accurately and quantitatively, and to visualize of the sequential transition of brain damage and recovery.

An automated system that locomotion of a rat triggered stimuli in the deep brain has been developed to improve experimental efficiency in Brain-Machine Interface experiments. A pair of stimulation electrodes were placed in the lateral hypothalamus of the rat brain. The locomotion was optically detected by tracking LEDs attached on the skull of a freely behaving rat. The rat initially had a sham period of 15 minutes, followed by an active period of 15 minutes where biphasic spike trains were applied to the deep brain. Experiments were conducted for 2 or 3 sets of the above trials on 4 adult rats. Rats tended to walk voluntarily in the active periods, while one rat learned to obtain the stimuli by shaking its head instead of walking. The behavioral change rapidly ceased in the sham periods, which suggests that our method temporarily induced the locomotion without altering natural behaviors of the rat.

The our previous study suggests SSVEP is related to the resolution of a retina in human. However, it is difficult to clarify the resolution of a retina in human. Therefore, we clarify the relationship between the resolution of a retina in a goldfish and SSVEPs.In this paper, we propose an experiment considered against differences between human and goldfish.Human and goldfish have three differences. 1) The view angle. 2) The fovea. 3) The optic chiasm.We design the experiment presenting the visual stimulus considered against these differences.We propose the experiment under the following conditions. 1) The human is presented the stimulus with one eye. The goldfish is presented with both eyes. 2) We present them at eyes of the peripheral field. 3) We present them to the right visual field in the human and the right eye in the goldfish. We present to the other side as well.

In this study, our purpose is to elucidate features of the Steady-State Visual Evoked Potential (SSVEP) induced by flipping a checkerboard pattern. Generically, EEG signals have individual variability. However, SSVEPs have less individual than other EEG signals. We focus on relationship between some conditions on checkerboard patterns and the power of the SSVEPs.We change the size of a checkerboard pattern and the number of grid-squares in a checkerboard pattern. The size of checkerboard pattern is a 5.625 cm square, 4.5 cm square, 3.375 cm square, 2.25 cm square, and 1.125 cm square. The number of grid-squares in the checkerboard pattern is 3x3, 4x4, 5x5, 6x6, 7x7, 8x8, 9x9, and 10x10. As results, there are some types of patterns in the power of the SSVEPs in each subject. In addition, We check the repeatability of patterns in the power of the SSVEPs on another day.

Hemiplegic subjects often show abnormal gait such as a circumduction gait. It is difficult for the subjects to acquire practical walking ability because of the abnormal gait. A body weight supported (BWS) training has been used clinically to improve the symmetry of gait pattern. The purpose of this study was to evaluate a variation in the symmetry of gait pattern by applying a BWS lift to hemiplegic patients by using inertial sensors. In this report, gait with the BWS lift and foot drop correction by FES was measured with a hemiplegic subject. The BWS lift with FES foot drop correction improved the limping gait and the symmetry of the gait pattern, while limping gait was not improved only by the BWS lift.

In our research group, a rehabilitation system using pedaling wheelchair and functional electrical stimulation (FES) has been studied for rehabilitation of lower limbs. However, it is difficult to control lower limb movements accurately for adjusting cycling speed during FES cycling by only feedback fuzzy controller because of nonlinearity and large delay in muscle response. Therefore, we focused on using feedback error learning (FEL) for FES control. In this study, fuzzy controller was tested in the FEL by computer simulation with muscle model including nonlinearity and large delay. Although the FEL didn't work properly in the learning with the fuzzy controller, the fuzzy controller modified by including proportional term could decrease control error as the number of learnings increased.

We have studied about an EMG analysis system for an electric prosthetic forearm control. Our previous experiment for motion recognition yielded high recognition accuracy results. This experiment with the 48-channel EMG system used Monte Carlo Method to decide sensing electrode position, and linear discriminant analysis. And, we have found when four channel electrodes are attached to correct positions on the forearm, it is able to recognize motions of it. This objective of this study is the development of a wearable the four-channel EMG analysis system by using our previous experimental results. Therefore, we have done motion recognition experiment, to confirm that obtain high recognition accuracy even if 4-channel EMG system sensing at electrode positions determined by 48-channel EMG system. In conclusion, the present study has demonstrated that high recognition accuracy requires training for using EMG system, and we found out sufficient training period depend on examinee.

Myoelectric upper limb prosthesis has attracted attention in recent years because can be operated intuitively using EMG signal and its appearance is close to real hand.But it still has some problems such as its stability of contact condition or determination of the optimum position of electrodes. This study reports the Development of a socket integrated with array electrode for myoelectric upper limb prosthesis. This array electrode, which was made of conductive cloth, can cope with various shapes of stumps of amputees including children. The advanced socket integrated with the developed array electrodes has capabilities to determine the appropriate positions of electrodes without much considering the location. We prototyped a band type array electrode using fabric electrodes and this one is valid for detecting EMG signals for the control of myoelectric upper limb prosthesis.

Nowadays by advancement of display technology, any contents can be presented to walls, floors and ceilings. In the near future, people will be able to display favorite contents inside their private house, using this technology. In this study, we examine the application of this new display technology for healthcare. Exercise support program was picked as the experimental application, because of urgent needs to reduce medical cost of our society. To induce motivation for exercise, Microsoft Kinect was used to detect the player's motion and a short focus projector was used for presenting virtual objects in front of the player. EMG and acceleration of limbs were measured during the subject playing experimental program.

The toe that does not contact the floor in stable standing is called floating-toe. Many people think of the floating-toe as a problem. We defined pseudo-floating-toe (PFT) as the toe that does not contact the floor in double-leg standing even though there is no motion restriction on the toe. It is necessary to confirm whether PFT is used during unstable standing. The purpose of this study is to clarify whether PFT is used during unstable standing. Seventeen women (12 women without PFT and 5 women with right-fifth-PFT) participated in this study. The subjects were asked to keep right-one-leg standing (R-OLS) on the measuring plate. The load by right-fifth-toe during R-OLS was measured by the buried sensor in the measuring plate. The duration for analysis was 5 seconds. The results showed that PFTs of all right-fifth-PFT pushed the floor during OLS. The PFTs were used in an unstable standing.

The purpose of this study is to clarify a useful objective parameter for the assessment of the difference between stable-standing and unstable-standing during one-leg standing. Subject was requested to keep one-leg standing with his hands on his waist. The center of pressure (COP) position was obtained by Stabilometer. Unstable point (UP) is defined as the time when his hand left from his waist. The deviation in medio-lateral direction (adXi) was calculated by the absolute value of the difference between the each position of COP and the averaged COP position in medio-lateral direction. For the anterior-posterior direction, the adYi were calculated in the same way. For adXi and adYi, the difference between before and after UP was analyzed. A useful objective parameter for the assessment of the difference between stable-standing and unstable-standing during one-leg standing was the COP position deviation in the anterior-posterior direction.

This study investigates the temporal relation between the presence of recall question and stride length under dual-task walk using autoregressive exogenous (ARX) model. The ARX model is developed to estimate the response of stride length during the dual-talk walk. Each stride length is measured by a toe-mounted inertial sensor. Ninety-eight elderly subjects performed a recall question like the names of Japanese prefectures during 50 [m] walk, and eleven younger ones performed a more difficult task during 100 [m] walk. Most of step responses estimated by ARX model showed the local minimum value in the stride length immediately after the start of recall question. The time from the start of recall question to the local minimum value is around 2.5 [s] and has no significance between elderly subjects (n=23) and younger ones (n=8). The recall question while walk causes rapid decrease in stride length and may increase of risk of fall.

We are developing a grip power feedback system for prosthesis user. In usually, a prosthesis user cannot know griping power of their hand. However, it is necessary for the hand user to grip something with appropriate grip power in their daily life. For this reason, the system which can feedback gripping power to the user was experimentally developed. In a previous system, it was difficult to control air pressure in real time. In order to improve this weak point, a positive pressure tank for improving rising characteristics of cuff pressure and negative pressure tank for increasing exhaust speed were provided in the air flow system. There change from a previous system made characteristics of air flow in new system improved strongly. However, the new system also has some problems such as air leakage from tanks. In this paper we would like to talk about the structure of our new system.

Ankle foot orthosis (AFO) is produced by modifying a positive plaster model. Because the modification is made by prosthetists' hand, the compatibility to the patient depends on the experience of prosthetists. The objective of the study is to develop an AFO design support system that enables manufacturing of highly compatible orthosis in a short term. The positive before and after modification were measured by 3D scanner. After defining the spline curve that go through the center of measured data from the top of lower thigh to toe, cross sectional data vertical to the spline curve were obtained. Obtained data were also approximated by spline and sectional curve is defined. By comparing the curve and area surrounded by the curve, the amount of modification were evaluated. In addition, the position of trim line used to generate orthosis shape was also able to define in each sectional curve.

Intubation, one of airway management, is an important procedure in surgical treatments. Recently video laryngoscopes are used for improving the view of anesthesiologists. However, anesthesiologists still have difficulties: in some cases such as morbid obesity and micrognathia, and the condition of the vision blocked by blood. Here we propose an intubation device which estimates the direction of trachea by detecting respiratory flow. We developed a prototype of intubation device and did a proof-of-principle experiment with a trachea model.

Continuous sensing of metrics for respiratory function, such as respiratory volume and oxygen intake, is useful for predicting disease and evaluating exercise capacity. Recently, respiratory sensing methods using the chest displacement were proposed as simple methods. However, the stability of measurement and the robustness to noise are the issues for the methods. This research proposes a method to detect the chest displacement by using electromagnetic induction to achieve respiratory sensing with the lower mechanical interference. Specifically, the electromagnetic induction between the coils attached to the chest is used to estimate respiratory volume with a regression model. Then, oxygen intake is calculated by using the estimated respiratory volume. For an evaluation experiment, respiratory volumes were recorded by using the proposed system and a calibrated spirometer. As a result, the estimation error was 15 % of the maximum respiratory volume. Moreover, the oxygen intake could be calculated from the respiratory volume.

Respiratory impedance measured by forced oscillation technique has been evaluated by average values during inspiratory and expiratory phases. However, it is well known that the impedance changes according to the airflow rate of a subject which changes during respiratory cycle. We should treat the impedance data as temporal data like electrocardiogram. Furthermore, the value of respiratory impedance is influenced by the heart beat which compresses the large airway located near the heart. Therefore, we should cancel the influence by heart beat in order to obtain precise information from the impedance data. We performed simultaneous recording of the respiratory impedance (MostGraph, Chest corporation, Japan) and finger-tip volume pulse wave (BSM-2353, NihonKoden, Japan), and obtained novel analysis methods for respiratory mechanics during rest breath.

This study proposes a chest sound-based wearable device for respiratory measuring and the monitoring of asthma. For the proper diagnosing and follow-up, measuring the respiratory is important when symptoms of asthma appear. The symptoms are convulsive, although asthma is a chronic disease. The symptoms could appear when the patients are in their homes or outdoor, so the proper finding of their severity is difficult. The main challenge here is the respiratory phase identification because of the high level of distortions to the signals from the artefacts during spontaneous breathing. To overcome this challenge and realize high noise stability, both the respiratory sound and the chest movements are used. To measure the chest movements, this device is formed from a flexible material. The results of a preliminary experiment and a phase identification experiment show the characteristics of signals and the possibility of identification by using proposed device.

This research proposes the automatic segmentation method of tongue region from head MRI to aid for Sleep Apnea Syndrome( SAS ) diagnose. This method calculates five feature values from the image which is trimmed around tongue from head MRI, and then that values are learned by Support Vector Machine( SVM ). As a result, accuracy rate which distinguished five images is about 55.7%, and the highest accuracy rate is about 74.08%. In order to improve accuracy, We utilize combined feature values, seek other efficient feature values in future.

Deep learning methods such as the Convolutional Neural Network and the Residual Network were applied to CT scan images in order to classify whether lung nodules become cancerous or not. Especially, the effect of changing the number of layers in the Residual Network was. Experiment were carried out using several models having these two network architectures and consisting of different numbers of layers and parameters.

After an outbreak of severe acute respiratory syndrome (SARS) in 2003, infrared thermography (IRT) systems were used as the border control strategies for fever screening of passengers at most major international airports. In this study, we proposed a visible/thermal image processing approach using only a CMOS camera-equipped IRT, thereby remote sensing of multiple vital signs for the rapid and accurate screening. Due to infection screening system expensive and required large-scale system structure, the system still has not reached yet the stage of widespread use. In this regard, we focused on minimum the hardware requirements to achieve a system that more suitable for real-world settings. The system displays the results via the logistic regression discriminant function derived from the heart and respiration rate, and body temperature within 10 seconds. The system achieved a sensitivity and specificity of 87.5% and 91.7%, which is notably higher compared to conventional fever based screening.

Implantable artificial lung have not been developed yet although extracorporeal membrane oxygenation system has been already in clinical use. This may be because the alveolar structure is too fine and complicated to be artificially made and manipulated. I presented the gas-exchange simulation using a 4D alveolar model at the 55th annual meeting, and revealed that the huge surface area corresponding to a tennis court is unnecessary for human beings and that the fine alveolar structure is required not for gas-exchange but for the lung elastic recoil. Based on this simulation result, I proposed a computational design of an implantable artificial lung.

In 2015, Tohoku University, the University of Tokyo, and Osaka University launched Japan Biodesign in collaboration with Stanford University to develop the leaders in medical/healthcare device innovation. Japan Biodesign fellowship program, namely, the very intensive practical training program, was developed based on Stanford Biodesign program that had already demonstrated the remarkable outputs, and started in Japan from Oct., 2015. During this 10-month program, the fellows identify problems/needs in clinical settings, invent solutions, and make business plans toward actual business implementation, The 1st batch fellows completed the program last July, and the 2nd batch fellows are working for their projects in the program now. In this presentation, I would like to talk about what Japan Biodesign is, what Japan Biodesign has done so far, and how Japan Biodesign expands in the future. Also, I would like to share the activities, outputs, and future visions of Osaka University regarding the program.

Japan biodesign program is the Japanese version of Stanford biodesign, which is an education program to develop leader of medical device innovation. The characteristics of the program is an approach that they start from clinical observation, extract a well-characterized need, and create concepts. On the other hand, because we have only two years' experiences, we need to discuss how to apply the method based on American medical system to Japan and how to use it in the Japanese ecosystem. I am engaged in the second budge (2016-17) of Japan biodesign fellowship. I think that not only we can learn systematized knowledge related to medical device development, but also we can create needs and concepts which are useful for business implementation in a short term. In this presentation, I will introduce the contents and progress of our fellowship activities and discuss the present state and future prospect of the program.

We are presenting our innovation infrastructure to find medical needs in the hospital (Tohoku University Hospital bedside solution program, Academic Science Unit: ASU) and the robust method to descriminate the needs worth working and challenging for business development.

In this session, we will update Japan Biodesign's global activities.

The titanium mesh has been applied to the EvaHeartTM and we have studied a tissue inducing electrode using it. In this study we studied histological characteristics of the titanium mesh for application to the artificial heart. The titanium mesh we used has diameter of 5 mm and thickness of 1.5 mm with an average pore size of 200 μm and 87% porosity. The titanium mesh whose one surface was covered with the silicone rubber was implanted under the skin of the rats, and it was extracted 12 weeks after implantation. The titanium mesh was filled with collagen, fibroblasts, but the connective tissue was not always good condition, because capillaries were localized around it and connective tissue may be out of range of oxygen supply. The titanium mesh is suitable material for application of the artificial heart system, but its thickness is important to ensure oxygen and sustenance supply.

An agenda of the ventricular assist devices is the clot formation, to cause cerebral infarction. The clot formed at the boundary between artificial materials and the living body. We were tried to develop new medical material by regenerating biotissue into the artificial material. In this report, we develop new inflow cannula use with hybrid material, and observed concrescence about heart and hybrid material. The scaffold was implanted under the skin and the biotissues ware regenerated into the scaffold. The hybrid cannula was made with this hybrid material, and evaluate it use with helical flow ventricular assist device by animal experiment. After 3 month, the cannula was fused with cardiac muscle smoothly. Any clot was observed on the surface of the hybrid material and gap between heart and the material. Endocapillary cell was observed surface of the material. These results show the usefulness of the medical material.

Titanium(Ti) is widely used for various implantable metallic materials depending on their high biocompatibility. We also have studied Ti scaffold for applying inflow and outflow's cannula and blood contacting surroundings of VAD. To promote early new ingrowth of vascular intima, our concept is focusing on the structural improvement by the micro powder sintering, and the chemical modification of Ti surface by the hydrophilic urethane treatment. For evaluating those structural advantages to relate to the promotion of neointima, the porosity, the mechanical strengths and the tissue invasions, were studied. And also for checking the advantages with respect to the chemical modification of Ti, the hydrophilicity, the microscopic and the optical chemical analyses were conducted for our specimens. Those results indicated that by combining the advantages of the structural customizing and the chemical modifications, the composite Ti would be proposed as the promotive scaffold.

1.Objectives: Blood pumps are used at 1-2L/min for pediatric VADs and 0.05-0.2L/min for blood purification. The hemolysis index is defined in ASTM-F1841 as NIH=TotalFreeHb*100L/time/flow. And the flow is restricted to 5±0.25L/min. If this is extended to low flow region, NIH value increases in a hyperbolic manner though plasma color does not change. 2.Method: A MERA centrifugal pump was operated in a circuit filled with bovine blood at constant 200mmHg and flow was changed every 30min for 1-6L/min. The change rate of the TotalFreeHb, δTFHB, was recorded. Next, the flow rate is kept at 4L/min and rotational speed was changed every 30min for 1400-3000rpm. 3.Results: The δTFHB did not show any positive correlation to flow. It rather showed positive correlation to rotational speed.4.Conclusion: Hemolysis index should not be divided by flow but δTFHB be used as it is. If necessary, δTFHB had better be divided by rotational speed.

In recent years, computational fluid dynamics (CFD) has been used for the design of rotary blood pumps. The secondary flow in the pump, especially between the blades, can be simulated by CFD and more precise prediction of pump performance at design and off-design points can be made. The US Food and Drug Administration (FDA) is engaged in establishing guidelines for the usage of CFD in the research and development phase of medical devices in order to help speed up the FDA approval process. The utilization of CFD in the field of medical device development is expected to increase further. Here, we will introduce the usage of CFD analysis for the design of an axial flow blood pump as a right ventricular assist device.

The developed rotary blood pump has an inner permanent magnet DC brush-less motor structure. Impeller is supported by a retainer-less open bearing. In this study, we confirmed its operation, however, blood compatibility will be examined.

Nowadays, 10 years survivals implanted a ventricular assist device have been achieved. The achievements indicate hemo-compatibility of rotary blood pumps for artificial hearts have been excellently improved. However, since the observation methods inside blood pumps have not been developed, they have been used in clinical without the understanding of detail interaction between the devices and blood. Therefore, we have developed the optical imaging method using visible and near-infrared light for the blood clotting reaction and individual blood cells dynamics to evaluate the hemo-compatibility non-invasively and continuously. In this study, we will introduce the developed methods and the foresight for the development of future artificial hearts.

For holding the forearm artificial arm, the patient must pull and tighten a part of the belt. However, the pressure distribution becomes heterogeneous so that the patient could become the bedsore. In this paper, our motivation is to develop the upper arm cuff that can distribute the even pressure. We optimized the upper arm cuff design applied the compliant mechanism and compare with the conventional design to validate the feasibility study of the proposed design. We optimized the upper arm cuff based on the Dr. Kanno's design as the initial shape. In experiment, we measured the displacement of the structure. As a result, we identified the consistency between the experimental value and the optimized solution. Then, we measured the internal pressure using a variation index. We concluded that the compliant mechanism design could decrease the pressure dispersion more significantly than conventional design.

Teeth brushing is a very important for one's health to prevent diseases. It is a fundamental oral care technique in daily life. However, there are many elderly people and handicap people, who could not brush their teeth without assistance of helpers. Therefore, the purpose of this study is to develop automatic teeth cleaning mouthpiece robot. The most basic way to brush the teeth is to move teeth brush along the row of the teeth. Then an eccentric cam mechanism was designed to achieve the movement. A Wiper guide mechanism was also designed to change the linear motion to curve motion for following along the row of the teeth. A safety system was designed to prevent aspiration. Brushing will be automatically stopped, if the user lefts his/her jaw up from the jaw supporter.

Laparoscopic surgery is rapidly replacing the conventional open surgery because of its less invasiveness, improvement of postoperative quality of life, less pain and better cosmetic result. However, the current surgical instruments may cause internal interference with other instruments during the operation and blind spot may occur due to its mechanical structure. To solve these problems, we have been developing a multi-joint manipulator using smart materials called magneto-rheological elastomers (MRE) for the use of laparoscopic surgery. In this study, we devised a prototype manipulator based on the optimal structure obtained by the electromagnetic field analysis and examined the elastic property of MRE-ring installed in the joints. From the result obtained, it was demonstrated that the stiffness of the MRE could be controlled by changing the direction of magnetic field between "Attractive" and "Repulsive", suggesting the availability of MRE for controlling the stiffness of the joint of the manipulator.

It is expected to support surgical navigation by estimating the deformation of the whole organ from the deformation information of the partially observed organs in the surgical operation. In this study, we estimated the deformation of 3-dimensional elastic body simulated by nonlinear finite element method, assuming the situation of gripping organs with forceps and applying force to deform during endoscopic surgery. As an approach to learn deformation, we estimated the displacement based on the data using the regression with the kernel method. Kernel method allow to learn the displacement without depending on the initial value of parameters for learning and suppress learning time. In actual elastic deformation, observation can only be performed in a partial range, and the displacement of only few points can be tracked. So, we estimated displacement of whole elastic object from the displacement information of only the very few mesh vertices which were observable points.

Penetration depth of the light into human tissue depends on its wavelength because of optical characteristics. Narrow-band imaging has a potential to provide a variety of texture images depending on the penetration depth that can be useful for tissue tracking, while its imaging has been studied intensively for lesion visualization. This study aimed at developing a robust and dense deformation tracking method of organs for image-guided surgical intervention using narrow-band imaging. We proposed a novel template matching method with multiple layers consisting of different spectral narrow-band images as a coarse-to-fine approach. We analyzed and found the relationship between light wavelengths and spatial frequencies of images. We also conducted an experiment with a chicken liver to evaluate accuracy of matching and tracking. The results showed that the proposed method was more accurate compared with the methods with single spectral images. We also discussed the characteristics of the proposed method for tracking.

Endoscopic submucosal dissection (ESD) is a radical operation for early-stage cancer of the stomach, colon, and esophagus. In ESD, circumferential cutting of the surrounding mucosa of the lesion and submucosa dissection are performed using electrosurgical knives by scope motion. However, this technique is the requirement of long-term training for safe and short time procedures. To address the issue, we have developed a robotic system using a commercialized endoscope for intuitive operation in one hand. The system consists of three parts: one is a holder for the control body of an endoscope, a grasper of the flexible shaft, and a master controller with four degrees of freedoms. The holder has two-rotation mechanism for two dials of the endoscope. In this study, mechanical tests were performed as measurement of scope motion by sine signal motion. From the results, the robot can manipulate each axis of an endoscope within 200 msec delay.

A handy switch interface has been developed to allow a surgeon in a sterilized area to control a locally operated forceps manipulator with five-DOFs. The proposed interface with two switches for the selection of axes and the on-off control of the selected axis operated by an index finger is designed to be attached to commercial forceps with adjustable position. Two prototypes using a toggle switch with 1 DOF or an analog stick with 2 DOFs were made by a 3 D printer. Both prototypes consist of a small push switch for the selection of axes. The control time was evaluated while performing a task model using prototypes by five participants. The difference between task times was shown. Compared to former developed interfaces, security, tiredness and operability under control were indicated by all subjects. An ergonomic handy interface was designed that allows minimally invasive robotically assisted endoscopic surgery.

The slow oscillation (SO) of cortical EEG during deep sleep is involved in memory consolidation. Recently, it has been reported that auditory stimulation synchronized with spontaneous SO during sleep enhanced the SO and elevated performance of declarative memory in humans. However, detail properties including stimulus timing-dependency have not been clarified. In this study, to elucidate these properties, we developed an experimental system for mice that can generate auditory stimulus at arbitrary phase of SO. This system consists of two components; a microcomputer for real-time waveform analysis based on template matching and a DSP for auditory stimulus generation. Evaluation test using EEG signals recorded from the mouse neocortex during sleep demonstrated that the developed system works as designed. We will investigate phase-response characteristics of SOs and possible contribution to memory consolidation by animal experiments.

The influence of active noise control (ANC) on auditory impression for listening to a music other than a noise was observed by psychological measurement and magnetoencephalography (MEG) in a situation where both a noise and non-target sounds were mixed. 15-stimuli conditions were produced by applying 5- levels of ANC to three kinds of classical musics. In the psychological measurement, adverse effects of ANC were observed for the music with the lowest spectral centroid. Further, MEG measurement were carried out for this music and autocorrelation function (ANC) of spontaneous responses were estimated. Significant increases of the effective duration of the ACF, τe, were observed for the non-preferred conditions in the low-γ activities, indicating the increase of cognitive processing load on a subject for non-preferred conditions.

The evaluation of subjective impressions induced by environmental sounds using neurophysiological indices has been proposed in recent years. In this paper, we focus on the evaluation of HVAC (heating, ventilation and air conditioning) sounds, and models that predict subjective coolness/preference induced by time-varying HVAC sound from brain activities were constructed. First, magnetoencephalographic (MEG) measurements were carried out to measure brain activities while hearing HVAC sound with paired comparison task. Second, feature vectors representing time-frequency components of brain activities on the whole head were extracted from MEG data using the time-frequency analysis and nonnegative tensor factorization (NTF). And third, two kinds of predictive model were constructed from the brain feature vectors and comparative judgments to pairs of stimuli using a regression model or an SVM-based method. Evaluation experiments show that the SVM-based method is more effective than the regression model.

Aim of this study is to the relation between emotion accompanying visual stimulation and auditory steady state response (ASSR). We used International Affective Picture System (IAPS) as an emotional stimulus. The stimulus images presented with three categories of negative, neutral, and positive by valence value with 80 pieces respectively. The charp sound (100Hz to 10kHz) of 55dB was presented 40 times/s and binaural stimulation. Experimental setup followed that one block consisting of 1 second of control image and silence, 2 seconds of stimulus image and chirp sound was repeated 240 times, and stimulus images presented randomly. As a result, negative was significantly larger amplitude than neutral in ASSR average value. (N = 7, p<0.05) It is suggested that the ASSR amplitude may be one of measures for quantitative evaluation between neutral image and negative image.